In recent years, there has been a growing concern with respect to the increase in the number of burglaries of houses, apartments, offices, and the like. Many complex and expensive locking devices have been developed and installed in an attempt to prevent such burglaries or any undesired entry. Such locking devices include the so-called unpickable locks, chain locks, bars for doors, and the like. However, presently-employed locking devices have various drawbacks. For example, many of such locks can actually be picked by the experienced burglar, or such locks are expensive or bulky. In addition, as will be understood, the use of bars for doors is not only bulky but is also unsightly. Therefore, it has long been desired to develop a door-locking device which is highly reliable and secure but is also inexpensive and unobtrusive. There have been many attempts to provide such a locking device. For example, as shown in U.S. Pat. No. 1,061,269, there is a door-locking device which is attachable to the floor adjacent the door to be locked, wherein a portion of the device is movable into and out of the moving path of the door to be locked. In this patent, a removable block is placed between the door and the pivoting device to prevent the door from being opened. However, the removable block is not secured to the pivoting portion so that it is possible for the removable block to be knocked off of the pivoting support so that an intruder can gain entry. Accordingly, the type of locking device disclosed in this patent is not completely secure and reliable.
Broadly, it is an object of the present invention to provide a door-locking device which overcomes the aforesaid problems. Specifically, it is within the contemplation of the present invention to provide an improved door-locking device which is simple and inexpensive to construct, but which is highly reliable and secure in preventing an intruder from gaining entry through the locked door.
It is a further object of the present invention to provide an improved door-locking device which is simple to install and operate and eliminates the prior art problems of door locks which may be picked or broken to gain entry.